At about 2:45 a.m., Gentili said he received a call from a man asking whether he had heard of the shooting. As the TV producer began to respond, the person on the other end of the phone interrupted Gentili.

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(Published Sunday, June 12, 2016)

"I'm the shooter. It's me. I am the shooter," the caller said.

Gentili said the man told him he "did it for ISIS" and then started speaking in Arabic before eventually hanging up the phone. NBC News has not independently confirmed News 13's report.

The station's managing editor, according News 13, confirmed the caller's phone number matched that of the gunman, identified as Omar Mateen.